This invention relates to apparatus for disintegrating sheets of shreddable material and, more particularly for disintegrating sheets of wallboard.
Typically, wallboard is formed by a layer of gypsum sandwiched between layers of paper, paperboard or the like. A relatively small percentage of wallboard is defective when manufactured and must be disposed of by the manufacturer. In the past, defective wallboard has simply been dumped in landfills. Environmental concerns, however, have placed increased restrictions on the landfilling of wallboard. In addition, the defective wallboard contains materials which, if properly processed, are capable of being recycled and used in other building materials. Accordingly, many wallboard manufacturers have been breaking up defective wallboard in order to enable recycling thereof.
A rather primitive but widely used method of breaking up wallboard is to pile the wallboard on a floor and to run back and forth over the wallboard with a truck. This has several disadvantages in that it is slow and labor intensive, produces very disuniform break up of the material, is dirty and requires the broken up material to be scooped up for delivery to a further processing station.
A more recent method involves feeding the sheets of wallboard endwise into a grinding roller which is rotated at high speeds. This process also is dirty and, because a high speed grinding roll is required, chunks of wallboard fly out of the grinder in the form of high speed projectiles. This creates a dangerous operating environment and requires retrieval of the chunks which fly from the grinder. The process also is very noisy.